Performance analysis of three unit redundant system with switch and human failure using Copula distribution

Abstract

The performance of a three unit redundant system with the impact of switch and human failure has been studied. A system with the three identical units has been considered for assessment
of performance under 2 out of 3: G; policy. In the system, a switch is used to transfer load from one unit to another unit. All three units of the system are connected in parallel configuration and
working under 2-out-of-3: G; policy. The system can have two types of failure i.e. partial failure and complete failure. Partial failure degrades the efficiency of system; and the complete failure breakdown the system and stops its functioning. Switch failure and human failure are considered as complete failure. The system has two types of failure and two types of repair. General repair is employed to the partially failed system and Gumbel - Hougaard family copula distribution complete failed system. The system is studied by supplementary variable technique and various measures of reliability, such as availability, reliability, MTTF and profit functions have been discussed. Some particular cases have
been discussed by taking different failure rates.